A long-dormant national conversation about guns has reignited: some are calling for an assault weapons ban while other feel guns themselves aren't the root of the problem. So far the shootings have sparked several gun buy-back programs and even an anti-gun video organized by big-city mayors – but the NRA says it's the entertainment industry that is partly to blame. NBC's John Yang reports.

By Elizabeth Chuck and M. Alex Johnson, NBC News

The National Rifle Association’s call to put armed guards in every public school in America has further intensified the debate over how to protect our nation’s children in class, with some districts saying they’re preparing to take just that action and other educators cautioning that doing so sends the wrong message about education.

And short of giving teachers and officers their own guns, administrators across the country are desperate to find a way to keep their pupils safe. Locked vestibules with buzzers, emergency preparedness drills, stronger glass and surveillance cameras are among measures being considered after the massacre last week at Sandy Hook Elementary School.

The district of 7,500 pupils about 40 miles northeast of Pittsburgh had already gone to court to get a judge's approval to have at least one armed retired state trooper in every school. They were in place as classes resumed Monday after the mass shootings Dec. 14 in Newtown, Conn.

"We plan to have that on a daily basis from now on," Superintendent Michael Strutt told NBC station WPXI of Pittsburgh. By the time the next school year begins, every guard in the school system will be armed, he said.

The sense of urgency is undeniable, with a few districts willing to fight fire with fire, as in Butler. Schools in Marlboro, N.J., for example, will have armed officers in place by January, Mayor John Hornik told NBC News on Friday.

After a week of calls for tighter gun restrictions, the National Rifle Association called for putting more armed security officers in the nation's schools and expressed concerns about violence portrayed in video games, movies and music. NBC's Pete Williams reports.

State Sen. Joe Scarnati, a Republican representing northern Pennsylvania, said there was only one important question: "What do we do to protect our kids?"

"If it requires to put armed individuals in our schools to protect our kids, then we need to do that," Scarnati told NBC station WJAC of Johnstown.

But that idea doesn't sit well with other educators, like Tony Scott, superintendent of schools in Bellaire, Ohio, where a local firearms association said it would provide free shooting training to teachers after the Connecticut shootings.

Ronald Stephens, executive director of the National School Safety Center, a joint project of the U.S. Education and Justice departments, said there's no centralized database tabulating how many school systems have an official armed presence on campus, but he estimated it at 25 percent. He called the NRA proposal "unfeasible."

"We have to ask ourselves what kind of climate we want to create in our schools. Do we want our school campus to look like the Old West with people having sidearms attached to their hip, or do we want education to happen in a positive way?" Stephens told NBC News. "That's the hard part of this."

Michael Smerconish, author Steve Siebold and David Corn of Mother Jones debate the NRA's idea that more guns and armed teachers would curb gun violence.

Some administrators are looking elsewhere for solutions. After years of unlocked front doors and casual conversations about someday increasing security in the small school district of New Hartford, Conn., Superintendent Philip O'Reilly isn't wasting another minute.

Fearing a repeat of the tragedy in nearby Newtown, O'Reilly is planning to modify the district's school buildings so they each have a small, locked vestibule between the main entrance and the building's interior, which will hold visitors for screening.

O'Reilly wouldn't give the cost of these new entryways, but he said the money must be found.

"Cost is no longer the priority. Keeping kids safe is the priority," he said.

In some cases, parents are leading the charge.

"I've had superintendents and headmasters who have been fighting for a year or two trying to do this, and the parents have been fighting them hand and fist because they didn't understand, and now the parents are coming to the school officials saying, 'Why aren't you?'" said Michael Dorn, executive director of Safe Havens International, a nonprofit group based in Georgia that helps schools improve their crisis preparedness.

Michael Dorn of Safe Havens International relays tips on how schools and parents can keep kids safe.

Security experts recommend that school districts start with a security assessment. Because changing entryways or installing security cameras can be expensive, these experts said school systems need to figure out exactly what their biggest shortcomings are before plowing ahead.

"The number one request [schools have been asking for since Newtown] is to conduct a security assessment. We look at everything, from your written practices to the physical security devices and emergency plans," said Paul Timm, president of Illinois-based, school security consulting firm RETA Security.

He said his recommendations usually fall in two main areas.

"There are two categories that protect people better than anything else: access control, which includes a locked vestibule, running a closed campus, visitor management procedures; and communications.

Do we have public address systems, do we have telephones that are outfitted with emergency dialing instructions, do we have two-way radios?" Timm said. "Those two areas, more than cameras, more than metal detectors, more than burglar alarm systems, protect people."

Locked vestibules can literally stop an intruder in his or her tracks. As administrators have become more concerned about security, many schools have restricted access to just one main entry point in the hope of doing that, Timm said.

Another solution for safety-proofing schools: bullet-resistant glass. Timm recently helped a school in Hastings, Minn., replace all the tempered glass in the building with laminated glass after a student brought a gun to school, and the total cost was about $3,500.

But such a low dollar figure for security fixes is rare.

"A large percentage of our schools are not designed well for any of these things. Sometimes, something simple can be $5 million," Dorn said.

Federal funds for school safety — the Readiness and Emergency Management for Schools (REMS) project — were eliminated in March 2011. Now the money must come from local taxpayers.

"There's not much in the budget for security at all. I want to say that before Columbine, not many schools had a line item for security in their budget," Timm said.

One security measure that doesn't come with a hefty price tag is running drills with teachers, students and administrators for various scenarios.

"It prepares us to make life-and-death situations more quickly," Dorn said. "They have an opportunity do something like lock a door, move kids out of a classroom, and [if] for various reasons don't take that action, our casualty rate doubles or triples. The human brain works faster than my laptop to make those life-and-death decisions, but only if you've had the exposure to prepare you."

Andrew Mach of NBC News contributed to this report.

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